hi fifi..
my lad snapped the shin bone (tibia) and fractured the bone thats directly behind (fibula) when he was 5 years old.
he had been playing on "monkey bars". he was swinging below the bars with feet about 12" above the ground.
we can only assume that because he was wearing rubber soled trainers, and the area he landed on was also rubber (matting)that when he landed, he came to an instant stop and snapped the bones.
he was fitted with a full leg cast for six weeks. as with any injury to a kid it was a long and painfull recovery. some days he was ok to do what the hospital had told us, other days he was in agony.. i think you need to let him determine how bad his pain is and how much he thinks he can do each day.... dont make him work hard if he is hurting too badly..
i think the bone will heal well... it wasnt displaced so didnt need to be re-set...
the cast can become tight on a lad thats having growth spurts. it will become tight in some cases. (ive known this to happen twice)
im not a doctor and have no medical training, so i can only tell you what i know from my own experiences...
the lad should be ok if you follow the doctors advice........